Soil Temps and Disease Control

Yesterday, I asked Paul Koch (TDL Manager) how the soil temperatures may influence timing for control of our early season patch diseases. Here’s what he said (from vacation, nonetheless):

“Though soil temps are in many cases indicating that initial fungicide applications for important diseases such as summer patch, take all patch, and fairy ring should be applied soon I would recommend holding off unless there is recent history of significant infection at the site. The primary reason for this is the time required for both the plant to begin growing (and exude chemical signals to the fungi) and for the fungus to respond and begin growing and responding to the signals. The fungi have certainly begun responding, but now that temperatures have moderated any growth or infection by the fungi has likely dropped considerably. If a fungicide application has already been made, be prepared to make additional applications in the coming months.”